1. Field of the Invention
One or more embodiments of the present invention relate to encoding and/or decoding of image data, and more particularly, to an encoding and/or decoding system, medium, and method with spatial prediction and spatial prediction compensation.
2. Description of the Related Art
Conventionally, spatial prediction is required to encode image data. For example, intra spatial predictive encoding is a technique for predicting pixel values of a current block using spatial correlation of an image. To be more specific, the pixel values of the current block are predicted using a differential value of decoded pixel values of blocks that are adjacent to the current block and correlated with the pixel values of the current block.
FIG. 1 illustrates eight examples ({circle around (1)}-{circle around (8)}) for eight respective prediction directions for conventional spatial prediction. Referring to FIG. 1, pixel values of a row immediately above or on the left side of a current block are used to perform the spatial prediction in various directions.
However, since the conventional spatial prediction is performed using pixel values of blocks on the left of the current block, it becomes impossible to perform real time spatial prediction and encoding.
FIG. 2 illustrates a pipeline processing that cannot use such a conventional spatial prediction using pixel values of a row immediately above or on the left side of a current blocks. Pipeline processing is a technique for performing the spatial prediction of the current block immediately after performing the spatial prediction of a previous block. Here, in conventional Pipeline processing, the spatial prediction of the current block using pixel values of blocks on the left of the current block can only be performed by using pixel values of decoded blocks adjacent to the current block after performing the spatial prediction, transform and quantization, inverse quantization and inverse transform, and spatial prediction compensation of blocks adjacent to the current block. As illustrated in FIG. 2, the above mentioned conventional spatial processing is illustrated as not being possible in the illustrated conventional Pipeline processing. Thus, such conventional spatial processing can not be performed using pixel values of blocks on the left of the current block. Such a pipeline processing failure results in similar failures of a real time encoding and decoding of image data, resulting in encoding and decoding delays.
Moreover, if an error is generated during the spatial prediction of an image having edges, the spatial prediction will be performed based on the error, causing error diffusion and display quality degradation.